The present invention relates generally to connectors used to connect together differential signal circuits, and more preferably to a connector assembly for connecting together differential signal circuits that incorporates a latching signal circuits that incorporates a latching assembly to provide increased retention forces to maintain the connector assembly together in a metal state.
Connectors used in differential signal applications are known in the art. Some of these connectors arrange their terminals in a signal-signal-ground pattern. However, patterns such as these have problems with controlling the impedance of the connector through the mating and termination regions of the connectors. The impedance of the terminals can be controlled by using a triangular pattern, referred to as a xe2x80x9ctriadxe2x80x9d in U.S. Pat. No. 6,280,209, issued Aug. 28, 2001 to the assignee of the present invention. In these triads, two differential signal terminals and an associated ground terminal and arranged are arranged in a triangular pattern so that the terminals are positioned at the apexes of the triangular pattern. Using a number of these triads and inverting them so that some triangular patterns are upright and the intervening triangular patterns are turned upside down, or inverted is one way of increasing density of the terminals in connectors. This arrangement is disclosed in copending International Patent Application No. PCT/US02/18372, filed Jun. 11, 2001 and also owned by the assignee of the present invention.
However, in the connectors described in these patent or applications, the manner of engagement utilized is either housing-to-housing or shield-to-shield frictional contact. Although this sufficient to retain the connectors together in normal connections, it is not sufficient to retain the connectors together under rough connection and disconnection cycles, or bear the weight of heavier cables that contain multiple sets, such as six or more, of differential signal cables, each with their own associated ground. Retention of the connectors is important to maintain the connectors and their terminals together.
Accordingly, the present invention is directed to a differential signal connector assembly that uses xe2x80x9ctriadxe2x80x9d terminal arrangements and which has increased retention capabilities over the prior art.
It is a general object of the present invention to provide an improved differential signal connector that uses a plurality of xe2x80x9ctriadsxe2x80x9d of terminals for connecting with a mating connector, and which utilizes a latching system to retain the connectors in a mater condition after engagement.
Another object of the present invention is to provide a connector assembly for connecting a cable to a circuit board in which the connector assembly includes first and second connectors, the first connector being terminated to a plurality of differential signal wires (and grounds) in the cable and the second connector being terminated to a differential signal circuits on a circuit board, the two connectors of the assembly having a plurality of conductive terminals arranged in at least two rows that extend widthwise of the connectors, the terminals being arranged in distinct xe2x80x9ctriadsxe2x80x9d or triplets with two differential signal terminals and one associated ground terminal arranged at apexes of imaginary triangles, the imaginary triangles of which may be arranged in an alternating, or inverted sequence within the connectors and the first connector including at least two latching members disposed therein and extending lengthwise along the first connector housing body, the latching members being engageable with stop surfaces on the second connector.
Yet another object of the present invention is to provide the latching members in the form of two elongated latching arms, each of the latching arms having a retention end that engages one or more housing, or body, portions of the second connector and a latching end disposed along a latching arm that projects forwardly of the retention end, the latching end including, in one embodiment, a hook-shaped latch that is received within a slot formed in the first connector, the latching arms extending alongside the first connector body portion into the terminal mating area thereof, but fully enclosed with an exterior shell or shield so as to prevent damage thereto.
A still further object of the present invention is to provide a latching member having a cantilevered latching arm that extends forwardly alongside its connector body portion, the latching arm terminating in a latching hook and further having a withdrawal stop member formed thereon intermediate between the latching hook and the retention end of the latching member.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.